This site is a fabulous resource for mapping London. With hours of fun you can superimpose a couple of dozen different maps ranging from the late 1700’s to the early 1900’s over a modern map of London. I’d have loved to have this when I was writing The Singing Fire. Interestingly, they don’t have the maps produced by Charles Booth and his team, which I used for my research. Booth’s team mapped the streets of London, colour coding them by wealth: dark blue for the starving poor, light blue for the poor who had enough to eat but barely, pink for the lower middle class (who could afford a servant) and so on. At the time I used the maps in the university library, but they’re now available online along with Life and Labour in London and a comprehensive archive of material.